Detachable core substrate and method of manufacturing circuit board using the same

Abstract

A detachable core substrate and corresponding method include a primer coated metal foil laminated on a core, an insulation layer laminated on the primer coated metal foil, and a first metal foil laminated on the insulation layer. The primer coated metal foil, the insulation layer, and the first metal foil are successively laminated on an upper surface and a lower surface of the core to be symmetrical about the core.

What is claimed is: 
     
         1 . A substrate, comprising:
 a primer coated metal foil laminated on a core;   an insulation layer laminated on the primer coated metal foil; and   a first metal foil laminated on the insulation layer,   wherein the primer coated metal foil, the insulation layer, and the first metal foil are successively laminated on an upper surface and a lower surface of the core to be symmetrical about the core.   
     
     
         2 . The substrate as recited in  claim 1 , wherein the primer coated metal foil comprises, in an order from each of the upper surface and the lower surface of the core to farthest from the core, a carrier film, a release layer, a second metal foil, and a primer layer. 
     
     
         3 . The substrate as recited in  claim 2 , wherein a joint interface between the release layer and the carrier film and a joint interface between the release layer and the second metal foil are separation interfaces, separated during fabrication of a circuit board. 
     
     
         4 . The substrate as recited in  claim 1 , wherein the insulation layer is made of a prepreg material, in which glass fiber or carbon fiber is impregnated in a resin. 
     
     
         5 . The substrate as recited in  claim 2 , wherein at least one of the first metal foil and the second metal foil is a copper foil. 
     
     
         6 . The substrate as recited in  claim 1 , wherein the core, the primer coated metal foil, the insulation layer, and the first metal foil are laminated in a lump. 
     
     
         7 . The substrate as recited in  claim 2 , wherein an adhesive force at a joint interface between the primer layer and the insulation layer or between the primer layer and the second metal foil is between about 0.05 kgf/cm2 and 0.2 kgf/cm2. 
     
     
         8 . A method of manufacturing a circuit board, comprising:
 preparing a substrate comprising a primer coated metal foil, a first insulation layer, and a first metal foil, which are successively laminated on an upper surface and a lower surface of a core to be symmetrical about the core;   forming an inner circuit layer by etching the first metal foil;   sequentially forming a second insulation layer, a second primer layer, and a third metal foil on the inner circuit layer and the first insulation layer; and   removing the release layer from a substrate including the third metal foil.   
     
     
         9 . The method as recited in  claim 8 , wherein, in an order from each of the upper surface and the lower surface of the core to farthest from the core, further comprising:
 configuring the primer coated metal foil to comprise a carrier film, a release layer, a second metal foil, and a primer layer.   
     
     
         10 . The method as recited in  claim 9 , wherein the preparing of the detachable core substrate comprises:
 successively laminating the primer coated metal foil, the first insulation layer, and the first metal foil in a lump on both surfaces of the core so that the first primer layer is interposed between the second metal foil and the first insulation layer; and   compressing the lump.   
     
     
         11 . The method as recited in  claim 10 , wherein the first primer layer is provided in about 80% to 90% level of semi-cured state in the laminating of the lump. 
     
     
         12 . The method as set forth in  claim 9 , wherein, upon the removing of the release layer, a coreless type of circuit board is separated from both sides of the core having the carrier film formed thereon. 
     
     
         13 . The method as set forth in  claim 8 , wherein at least one of the first insulation layer and the second insulation layer is made of a prepreg material in which glass fiber or carbon fiber is impregnated in a resin. 
     
     
         14 . The method as set forth in  claim 9 , wherein at least one of the first metal foil, the second metal foil, and the third metal foil is a copper foil. 
     
     
         15 . A substrate, comprising:
 a primer coated metal foil comprising a carrier film, a release layer, a second metal foil and a primer layer laminated on a core;   an insulation layer laminated on the primer coated metal foil; and   a first metal foil laminated on the insulation layer,   wherein the primer coated metal foil, the insulation layer, and the first metal foil are laminated on at least one of an upper surface and a lower surface of the core.   
     
     
         16 . The substrate as recited in  claim 15 , wherein the primer coated metal foil, the insulation layer and the first metal foil are successively laminated in a lump on the at least one of an upper surface and a lower surface of the core so that the primer coated metal foil, the insulation layer, and the first metal foil are symmetrical about the core. 
     
     
         17 . The substrate as recited in  claim 15 , wherein the primer layer is interposed between the first metal foil and the insulation layer to tightly adhere the first metal foil and the insulation layer. 
     
     
         18 . The substrate as recited in  claim 15 , wherein the release layer is formed on the carrier film and is configured with a release force sufficient to enable release of the core.